Test  of  High  Duty  Pumping  Plant 
Under  Ordinary  Working 
Conditions* 


BY 

DABNEY.  H.  MAURY,  Jr.,  M.  E., 
Peoria,  III,. 


A paper  presented  at  the  Springfield  Meeting 
of  the  Illinois  Society  of  Engineers  and 
Surveyors,  January  27,  28,  29, 1897. 


* 


TEST  OF  HIGH  DUTY  PUMPING  PLANT  UN- 
DER ORDINARY  WORKING  CONDITIONS. 


DABNEY  H.  MAURY,  JR.,  M.  E.,  PEORIA. 


Tests  of  steam  pumping  plants  are  of  so  frequent  occurrence  as 
under  ordinary  circumstances  to  hardly  warrant  the  reading  of  a de- 
scription of  one  of  them  as  a paper  before  an  Engineering  Society. 

Tests  of  this  sort  of  machinery  are,  however,  generally  made  for 
acceptance;  and,  where  the  incentive  to  show  good  results  takes  the 
form  of  a bonus  in  case  of  success,  or  fines,  or  other  penalties,  or  even 
rejection,  in  case  of  failure,  no  effort  is  spared  to  make  the  plant  show 
the  best  efficiency  of  which  it  is  capable.  Expert  manipulators  of  the 
particular  class  of  machinery — generally  skilled  employes  or  the  man- 
ufacturers themselves — picked  firemen,  picked  coal,  perfectly  clean 
boilers,  carefully  selected  packings  and  lubricants,  repeated  trials  to 
determine  the  best  working  conditions  allowable  under  the  specifica- 
tions— all  combine  to  secure  results  which,  afterward,  in  actual  work- 
ing practice,  are  rarely,  if  ever,  attained. 

The  test  of  the  plant  of  the  Peoria  Water  Company,  which  forms 
the  subject  of  this  paper,  was  made  under  ordinary  working  condi- 
tions. No  effort  was  made  to  improve  the  condition  of  any  part  of 
the  boilers,  pumps  or  auxiliaries  in  any  way  whatever  for  the  trial. 
The  boilers,  which  are  generally  cleaned  about  once  every  five  or  six 
weeks,  had  been  running  nearly  that  time  when  tested,  and  owing  to 
recent  deterioration  in  the  boiler  compounds  used,  were  much  more 
coated  than  usual  with  scale  and  were  leaking  slightly.  The  plant 
had  been  in  operation  a little  over  five  years.  There  were  some  small 
leaks  in  valves,  pipes  and  stuffing  boxes.  The  regular  engineers  and 
firemen  were  employed.  No  attempt  was  made  to  alter  steam  press- 
ure nor  cut-off,  notwithstanding  the  fact  that  it  was  known  that  these 
were  not  at  the  point  of  highest  efficiency. 

It  was  the  writer’s  desire  to  test  the  whole  plant  just  as  it  was  or- 
dinarily operated,  with  a view  to  determining,  as  nearly  as  possible, 
the  direction  in  which  improvements  could  be  made.  One  of  the 
principal  benefits  which  it  was  hoped  might  be  derived  from  the  tests, 


2 


was  the  improvement  of  the  feed-water  return  system,  with  a conse- 
quent reduction  in  cost  of  boiler  compounds  and  saving  of  oil,  and 
better  performance,  fewer  repairs  and  longer  life  of  boilers. 

While  no  other  test  has  been  made  since  the  one  to  be  described, 
the  operation  of  the  plant  in  the  meantime  has  shown  to  a certain  ex- 
tent some  of  the  improvements  resulting  from  the  changes  made,  and 
the  paper  will  include  a brief  description  of  these  changes  and  of  the 
results  obtained. 

DESCRIPTION  OF  PLANT. 

The  plant  tested  was  the  steam  pumping  plant  of  the  Peoria 
Water  Company,  which  consists  of: 

Three  Worthington  Compound  Condensing  Duplex  Vertical 
High  Duty  Pumping  Engines,  rated  at  7,200,000  gallons  capacity 
each  per  twenty-four  hours,  at  piston  speed  of  140  feet  per  minute. 
The  pumps  are  numbered,  respectively,  61 1,  612  and  613. 

Three  batteries  of  Heine  Water  Tube  Boilers,  each  battery  having 
two  boilers  of  200-horse  power  each,  or  1,200-horse  power  in  all  six 
boilers.  The  boilers  are  numbered  from  east  to  west  and  from  1 to  6. 

And  the  following  auxiliary  pumps,  compressors,  etc.: 

Pumps  Nos.  1 and  2. — Boiler-feeders.  These  are  located  one  on 
each  side  of  hot  well  and  between  boilers  Nos.  4 and  5,  and  exhaust 
into  hot  well. 

Pumps  Nos.  3,  4 and  5. — Air  compressor  and  water  pumps,  with 
high  pressure  water-plungers  attached  to  yokes  on  the  piston  rods. 
These  pumps  are  set  on  brackets  on  engine  room  wall  and  exhaust 
into  hot  well. 

Pumps  Nos.  6 and  7. — Used  to  return  condensed  jacket  steam  to 
boilers;  are  located  on  first  floor  of  main  pump  grating,  and  exhaust 
into  hot  well. 

Pump  No.  8. — Used  for  draining  pump-pit  or  dry-well,  and  lo- 
cated at  bottom  of  same,  exhausting  into  sewer. 

Pumps  Nos.  9 and  10. — Used  to  create  vacuum  in  condensers, 
and  to  pump  condensed  steam  from  main  engines  up  into  the  hot 
well.  Are  located  at  bottom  of  dry-well,  about  on  a level  with  con- 
densers, and  exhaust  into  hot  well. 

Pump  No.  11. — Duplex,  Two-Stage  Air-Pump,  made  by  New 
York  Air  Brake  Company,  and  known  as  their  “No.  3 Duplex 
Pump.”  Used  for  compressing  and  pumping  air  into  accumulator 
tank  and  air  chamber  on  force  main.  Is  set  against  wall  of  engine 
room,  and  exhausts  into  hot  well. 

And  one  5xio-inch  Horizontal  Automatic  Cut-off  Engine,  built 
by  John  T.  Noye,  Buffalo,  and  used  only  for  driving  dynamos  to  fur- 
nish electric  light.  This  is  located  in  a corner  of  engine  room,  and 
exhausts  into  sewer. 

There  is  a steam  trap  for  returning  into  the  hot  well  the  steam 
condensed  in  main  steam  lines. 


View  of  Boiler  Room,  Pumping  Station  of  the  Peoria  Water  Co. 


View  of  Engine  Room,  Pumping  Station  of  the  Peoria  Water  Co. 

Showing  Worthington  Pumping  Engines  Nos.  611,  613  and  613.  The  Mercury  Column 
is  shown  against  the  wall  at  the  right  of  the  picture. 


View  of  Engine  Room,  Pumping  Station  of  the  Peoria  Water  Co. 

Showing  Electric  Light  Engine  and  Dynamo,  and  Air  Compressor  Pumps  Nos.  3,  4,  5 and  11. 


3 


The  three  condensers  are  of  the  surface  type,  and  are  set  one  on 
each  suction  pipe  of  the  main  engines,  at  the  bottom  of  the  dry-well. 
Over  the  hot  well,  which  is  located  in  an  alleyway  between  boilers 
Nos.  4 and  5,  is  a closed  heater.  Exhaust  steam  from  the  auxiliaries 
(except  that  from  No.  8 and  the  electric  light  engine),  goes  into  the 
closed  heater,  where  it  imparts  some  of  its  heat  to  a coil  through  which 
the  feed-water  is  being  pumped  on  its  way  to  the  boilers,  and  thence 
passes,  partly  condensed,  down  into  a coil  of  pipe  in  the  hot  well, 
where  its  condensation  is  completed  by  the  feed-water  which  sur- 
rounds it.  This  feed-water  is  principally  the  condensed  steam  from 
the  main  engines  and  auxiliaries,  the  deficiencies  due  to  leakage,  ex- 
hausts not  returned,  etc.,  being  made  up  by  the  admission  of  fresh 
cold  water  from  the  mains.  The  boiler-feeders  draw  this  feed-water 
from  the  hot  well  and  pump  it  through  the  coil  in  the  heater,  just  de- 
scribed, into  the  boilers. 

As  but  one  main  pumping  engine  is  ordinarily  required  to  supply 
the  city  with  water,  the  test  was  made  on  one  pump  only,  which  was 
No.  612.  Boilers  Nos.  5 and  6 alone  were  used.  The  electric  light 
engine  was  not  run,  nor  were  pumps  Nos.  3 and  4 (compressors); 
pump  No.  7 (jacket-pump);  pump  No.  8 (dry-well  pump),  nor  pump 
No.  9 (vacuum  pump).  Pump  No.  2 was  used  only  to  deliver  feed- 
water  from  the  hot  well  into  the  barrels  in  which  it  was  weighed,  and 
whence  it  was  drawn  by  pump  No.  1 and  forced  through  the  heater 
into  the  boilers. 

The  accompanying  photographs  give  an  idea  of  the  general  ar- 
rangement of  the  plant. 

DESCRIPTION  OF  TESTING  APPARATUS  AND  PREPARATION  OF  SAME. 

Much  time  and  attention  were  given  beforehand  to  the  standard- 
ization of  thermometers,  pressure  and  vacuum  gauges,  scales  and 
other  instruments,  and  in  this  direction  it  was  found  necessary,  in  the 
absence  of  laboratory  facilities,  to  devise,  in  some  instances,  apparatus 
for  the  purpose. 

Thermometers. — A Centigrade  Thermometer,  made  of  Jena 
Normal  Glass,  reading  from  o°  to  ioo°,  and  graduated  to  tenths  of 
i°  C.  was  purchased,  and  was  sent  to  Yale  Observatory  for  test.  By 
means  of  the  certificate  of  corrections  furnished  by  the  observatory, 
this  thermometer  could  be  used  as  a standard  of  comparison  between 
the  limits  of  its  graduations.  Another  thermometer  graduated  to 
fifths  of  i°  C.,  and  reading  from  ioo°  to  200°  C.,  was  used  for  com- 
parisons at  higher  temperatures.  A sufficient  number  of  cheaper 
thermometers,  suitably  graduated,  were  also  purchased.  A mercury 
well  71^  inches  long  by  1 y2  inches  inside  diameter,  was  set  vertically 
inside  of  a 4-inch  pipe  which  was  closed  at  top  and  bottom  and  fitted 
on  one  side  with  a valve  for  the  admission  of  steam,  and  a valve  for 
the  admission  of  cold  water;  and  on  the  other  side,  near  the  top,  with 


4 


an  outlet  valve.  By  means  of  this  4-inch  jacket  the  mercury  well 
could  be  surrounded  by  a bath  at  any  desired  temperature  from  120  C., 
the  temperature  of  the  well  water,  up  to  170°  C.,  the  temperature  of 
steam  at  the  maximum  boiler  pressure.  The  thermometer  to  be 
tested  was  suspended  in  the  mercury  well  with  the  standard  thermom- 
eter, the  bulbs  being  at  the  same  level,  and  the  mercury  was  stirred 
till  its  temperature  was  practically  uniform,  when  simultaneous  read- 
ings were  taken.  Fifteen  to  twenty  readings  were  taken  at  each  ob- 
servation, and  observations  were  made  for  each  50  C.  To  each  ther- 
mometer was  attached  a numbered  tag,  and  the  record  of  its  test  was 
made  on  blanks  prepared  for  the  purpose,  and  of  which  the  accompa- 
nying blank  is  a sample. 

Standardization  of  Thermometer  by  Comparison  with 
Standard  Thermometer. 

Maker  and  No.  of  Standard  Thermometer 

Maker  and  No.  of  Thermometer  Compared 


Date 189..  Observers 


No. 

Reading  of 
Standard 
Thermom- 
eter. 

Correction 

for 

Standard. 

Actual 
Tempera- 
ture of 
Well. 

Reading  of 
Thermom- 
eter 

Compared. 

Correction 
for  Ther- 
mometer 
Compared. 

REMARKS. 

Pressure  and  Vacuum  Gauges  and  Indicator. — There 
are  about  twenty-five  pressure  gauges  and  three  vacuum  gauges  in  use 
at  the  plant,  the  majority  of  which  were  used  during  the  test.  An 
attempt  to  compare  these  gauges  with  the  standard  gauge  at  the 
pumping  station  developed  the  fact  that  the  latter  was  itself  incorrect, 
as  were  also  the  only  other  so-called  standard  gauges  available  in 
Peoria;  and  as  it  was  important  that  the  gauges  should  be  accurately 
standardized,  efforts  were  made  to  find  a mercury  column.  Diligent 
search  by  the  writer  in  Chicago  failed  to  discover  one;  and  the  litera- 
ture on  the  subject  seemed  also  to  be  deficient.  Only  one  type  of 
column  was  found  to  be  described.  In  this  type  the  level  of  the  mer- 
cury in  the  reservoir  could  not  be  seen,  and  it  was  necessary  to  calcu- 
late the  same  from  the  height  of  mercury  in  the  column.  This  made 
it  essential  that  the  glass  column  should  be  of  uniform  bore.  It 
seemed  that  a much  better  and  cheaper  instrument  might  be  con- 
structed, and  accordingly  one  was  finally  devised  by  the  writer  and 
made  by  him  and  by  the  regular  employes  at  the  pumping  station, 
out  of  ordinary  pipe  and  fittings  and  common  glass  tubing. 


5 


In  the  Peoria  Water  Company’s  mercury  column  the  level  of  the 
mercury  in  the  well  can  be  seen;  irregularities  of  bore  of  tubing  do 
not  affect  the  reading,  and  no  corrections  of  any  sort  are  necessary, 
save  for  temperature.  As  the  column  is  located  inside  the  building 
where  the  temperature  does  not  vary  more  than  20°  throughout  the 
vear,  even  this  correction  is  rarely,  if  ever,  needed.  The  column 
answers  every  purpose  better  than  the  expensive  instruments  de- 
scribed in  works  which  treat  of  them,  and  can  be  used  with  either  air 
or  steam  or  water  pressure. 

The  record  of  the  comparison  of  each  gauge  with  this  mercury 
column  was  made  in  duplicate,  one  copy  being  pasted  to  the  back  of 
the  gauge  and  the  other  left  in  the  record  book.  Below  is  found  a 
sample  of  blank  form  for  record: 


Standardization  of  Pressure-Gauge  by  Comparison  with 
Mercury  Column. 


Maker  and  No.  of  Gauge 


Date 


Temperature  of  Mercury 
Barometer  in  Room  .... 


No. 

Mercury 
Column, 
in  inches 
(Observed)' 

Mercury 
Column, 
in  inches 
(Corrected) 

Mercury 
Column, 
in  Pounds. 

Gauge  in  Pounds. 

Correction 
in  Pounds. 

REMARKS. 

Up. 

Down 

Mean 

One  inch  Mercury  @ 70  degrees  Fahr.=o.493  lbs. 
One  inch  Water  @ 70  degrees  Fahr.=o.c>36i  lbs. 


The  Taber  Indicator  used  in  the  test  was  standardized  by  means 
of  the  same  mercury  column.  The  vacuum  gauges  were  tested  with 
a mercury  manometer,  made  of  a plain,  straight  glass  tube,  one  end  of 
which  was  coupled  by  means  of  a short  piece  of  rubber  tubing  to  the 
pipe  on  which  the  gauge  to  be  tested  was  set.  The  other  end  of  the 
tube  was  immersed  in  a glass  beaker  of  mercury,  and  a common  yard 
stick  tied  to  the  tube  gave  the  readings  in  inches  of  mercury.  The 
results  were  recorded  on  blanks  similar  to  those  used  for  the  pressure 
gauges. 

Scales. — There  were  used  in  the  tests  two  large  rolling  mill 
scales,  on  wheels,  for  weighing  feed- water;  one  dormant  warehouse 
scale  or  platform  wheelbarrow  scale,  for  weighing  coal;  one  smaller 


6 


platform  scale  for  weighing  Calorimeter  condensing  water,  and  one 
small  grocer’s  scale  for  weighing  the  small  amount  of  condensed  water 
coming  from  the  Calorimeter.  All  of  these  scales  were  previously 
tested  by  the  local  weighmaster  and  the  writer,  and  a table  of  correc- 
tions for  each  made  out. 

Calorimeter. — The  Barrus  Continuous  Flow  Calorimeter,  as 
described  on  page  380,  Carpenter’s  Text  Book  of  Experimental  En- 
gineering, was  used  during  the  test,  and  the  results  were  afterwards 
checked  by  the  ordinary  barrel  Calorimeter.  In  this  connection  it 
should  be  stated  that  the  results  given  by  the  Barrus  Calorimeter 
showed  superheated  steam ; but  as  it  was  found  very  difficult,  under 
the  existing  circumstances,  to  get  a reliable  figure  for  the  constant  flow 
of  the  Calorimeter,  and  as  it  was  deemed  improbable  that  there  was 
superheat,  the  results  were  disregarded  and  the  steam  was  assumed  as 
dry — an  assumption  which  later  observations  have  shown  to  be  ap- 
proximately correct. 

Coal  Analysis. — A sample  of  coal  was  taken  from  each  wheel- 
barrow, and  from  all  of  these  small  samples,  after  crushing  and  care- 
ful mixing,  a sample  of  several  pounds  was  secured.  All  of  this  was 
powdered,  passed  through  a fine  screen,  and  a sample  from  this  was 
taken  for  analysis  by  Dr.  Theodore  Breyer,  of  Peoria,  with  the  fol- 
lowing results: 


Moisture 

...  7 

45 

per  cent. 

Ash 

. . . 12 

49 

u 

Carbon 

•••59 

55 

u 

Hydrogen 

•••  3 

42 

a 

Sulphur 

•••  3 

90 

a 

Oxvgen  and  nitrogen.  . . . 

. ..  13 

l9 

u 

100.00  per  cent. 

Repeated  approximate  analyses  of  the  sample  gave  the  fixed  car- 
bon in  the  fuel  as  42.95  per  cent.,  and  the  fixed  carbon  (or  “fixed 
combustible,”  as  suggested  by  Dr.  Emery)  in  the  coal,  dry  and  free 
from  ash,  as  54  per  cent. 

Calculations  of  the  heating  value  of  the  fuel  from  the  ultimate 
analysis  by  Dulong’s  law  showed  results  varying  from  9,645  B.  T.  U. 
per  pound  of  fuel,  up  to  9,903  B.  T.  U.  per  pound  of  fuel,  according 
to  the  figures  used  for  the  heating  values  of  the  several  elements,  and 
the  method  of  applying  the  formula.  The  lowest  figure,  9,645  B.  T. 
U.,  was  obtained  by  using  the  formula  given  in  Article  344  of  Car- 
penter’s Text  Book  of  Experimental  Engineering,  and  allowing  for 
the  latent  heat  of  evaporation  of  the  water  formed  by  the  combustion 
of  the  hydrogen.  The  highest  figure,  9,903  B.  T.  U.,  was  obtained 
by  applying  Berthelot’s  figures  in  Dulong’s  formula  as  given  in  foot 
note  to  page  633  of  Kent’s  Mechanical  Engineers’  Pocket  Book,  and 
not  allowing  for  the  latent  heat  of  evaporation  of  the  water  formed 


1 


by  the  combustion  of  hydrogen.  An  average  of  all  the  results  as  fig- 
ured from  the  ultimate  analysis  gives  9,750  B.  T.  U.  per  pound  of 
fuel. 

But  the  calculations  of  the  heating  value  of  the  same  sample  from 
the  proximate  analysis,  as  in  the  table  on  page  634  of  Kent’s  Pocket 
Book,  show  much  higher  values,  the  figures  being  10,830  B.  T.  U. 

In  the  tabulation  of  the  results  of  the  test,  Items  27,  28,  29,  30, 
63  and  68  show  separate  results  based  on  each  of  the  two  calculations 
of  heating  value,  and  their  wide  variation  (over  11  per  cent.)  clearly 
illustrates  the  possible  error  in  any  given  method  of  arriving  at  the 
thermal  value  of  this  sort  of  fuel  by  calculation  based  on  its  chemical 
constituents. 

Flue  Gas. — A flue  gas  sampler  was  constructed  of  a net  work 
of  14 -inch  perforated  pipe,  this  being  so  distributed  over  the  whole 
area  of  the  flue,  as  to  insure  the  collection  of  a fair  sample  of  the 
gases  passing  along  to  the  stack.  An  iron  door  was  built  across  the 
flue  between  boilers  4 and  5,  so  that  no  air  could  get  into  the  flue 
except  what  passed  through  the  settings  of  boilers  5 and  6. 

As  the  chemical  apparatus  for  testing  the  flue  gases  could  not  be 
made  to  work  satisfactorily  on  the  day  of  the  test,  the  analysis  of  the 
gases  is  not  given  here.  Tests  made  afterwards,  however,  under  as 
nearly  as  possible  similar  conditions,  showed  a slight  excess  of  free 
oxygen  in  the  flue. 

The  Temperature  of  Flue  Gases  was  determined  by  a high 
temperature  thermometer  kindly  loaned  by  the  University  of  Illinois. 

The  Draft  was  measured  by  an  U-tube  manometer. 

The  Temperature  of  the  Furnace  was  not  taken  because 
of  lack  of  suitable  instruments. 

The  Aneroid  Barometer  used  to  determine  the  atmospheric 
pressure  was  compared  with  the  mercurial  barometer  of  the  local 
Government  weather  observer. 

The  apparatus  used  tO  weigh  the  feed-water  consisted  of  two 
large  rolling-mill  platform  scales,  each  supporting  a tierce  of  capacity 
of  about  250  gallons.  These  tierces  were  alternately  filled  by  the 
boiler  feeder  No.  2,  which  pumped  water  from  the  hot  well  into  the 
top  of  the  tierces.  After  the  full  tierce  had  been  weighed,  it  was 
allowed  to  discharge  into  a third  tierce  which  lay  on  the  floor  between 
the  two  scales;  and  from  this  tierce  the  water  was  pumped  by  No.  1 
boiler  feeder  through  the  heater  into  the  boilers.  The  total  feed- 
water  pumped  was  accurately  weighed  in  this  way,  while  that  pro- 
portion of  this  total  which  consisted  of  fresh  water  from  the  mains 
fed  into  the  hot  well  to  make  up  the  deficiencies  caused  by  leakage, 
etc.,  was  measured  by  a water  meter  which  was  repeatedly  tested. 

The  jacket  steam  and  steam  returned  by  the  trap  were  .deter- 
mined by  carefully  noting  all  the  conditions  of  operation  of  jacket 
pumps  and  trap  during  the  test,  and  afterwards  running  the  jacket 
pump  and  trap  under  similar  conditions,  except  that  the  returned 


8 


steam  and  water  were  discharged  into  barrels  partly  filled  with  cold 
water,  the  increase  in  weight  and  jtemperature  of  the  water  being 
noted. 

For  determining  the  head  against  which  the  main  pumping 
engine  was  working,  the  readings  of  the  gauge  were  checked  by 
means  of  the  known  difference  in  levels  in  the  well  and  in  the  reser- 
voir, the  friction  in  mains  being  added  to  this  difference  in  head.  The 
calculations  for  main  friction  were  themselves  checked  by  a large 
number  of  readings  of  a gauge  on  the  force  main,  taken,  first,  when 
the  pumps  were  idle,  and  then  when  they  were  working  under  the 
conditions  of  the  test. 

To  determine  the  leakage  of  the  valves  in  the  water  cylinder, 
the  heads  of  the  upper  and  lower  force  chambers  were  alternately 
removed,  and  the  water  flowing  past  each  set  of  suction  and  discharge 
valves  was  led  into  a bucket  of  known  capacity  and  the  time  of  filling 
noted.  The  leakage  past  the  plungers  was  determined  in  somewhat 
the  same  way,  except  that  a weir  box  and  hook  gauge  were  used  to 
measure  the  water.  Observations  were  made  with  the  plunger  at  the 
end,  and  at  the  middle  of  the  stroke. 

The  steam  used  by  the  several  auxiliary  pumps  was  determined 
by  running  the  respective  pumps,  after  the  test,  under  as  nearly  as 
possible  the  conditions  as  to  speed,  steam  pressure,  load  and  back- 
pressure, which  obtained  during  the  test.  The  steam  was  exhausted 
under  the  proper  pressure  into  a large  tierce  partly  filled  with  water, 
and  the  increase  in  weight  and  temperature  of  the  water  in  the  tierce 
noted.  While  the  weights  thus  obtained  are  known  to  be  fairly  cor- 
rect, not  so  much  confidence  could  be  placed  in  the  determination  of 
the  temperature,  as  it  was  difficult  to  so  stir  the  water  in  the  large 
tierce  as  to  secure  a fair  reading  on  the  thermometer.  The  inaccura- 
cies, however,  are  not  important,  as  they  could  not  appreciably  affect 
the  general  result. 

The  work  performed  by  the  several  auxiliaries  was  calculated  in 
each  case  from  the  observed  conditions. 

The  strokes  of  the  main  pump  were  given  bv  the  counter  at- 
tached thereto,  which  was  checked  repeatedly  and  always  found  cor- 
rect. The  indicator  cards  were  taken  in  turn  from  the  upper  and 
lower  sides  of  the  high  and  low  pressure  pistons,  in  each  of  the  two 
engines  composing  the  No.  612  Duplex  Pump.  Four  complete  sets 
of  cards,  eight  cards  in  each  set,  were  selected  from  those  taken  dur- 
ing the  test.  The  mean  effective  pressure  was  figured  from  these 
cards  by  measuring  the  area  with  the  simple  little  Planimeter  shown 
herewith,  invented  and  patented  by  John  Goodman,  of  Leeds,  Eng- 
land. 

During  the  test,  the  several  observers  were  stationed  as  follows: 

Two  men  weighed  the  coal,  both  keeping  tally,  and  checking  re- 
sults after  each  wheelbarrow  was  weighed.  These  men  also  read  and 
recorded,  every  fifteen  minutes,  the  temperature  and  draught  of  flue 


# / S,  o/e 


’•  'r 


/Z 


(S) 


0 

O 

£ 

w 

hH 

£ 

0 

w 

Oh 


Diagram  from  Pump  No £/J  Cylinder  To/,  h.f 

Diameter  of  Cylinder..<?4  ; Diameter  of  Rod  2>'/z  ; Stroke. .37.  Clearance 

Date—A£oLy.~JS?. i Sg6.  ; Time  4 «>.  ; End  of  Cylinder  ; Scale  of  Spring  SQ^j, 
Boiler  Gauge,.  J<27-..^  Vacuum  Gauge  Z63/+ ..  ; Rev.  per  minute.  2/.‘/z..„ 


< K 
Sio 

M < 

4 1 o 

\ i 

w 

Qh 


/q  CsJ  # f Stc/e. 

Diagram  from  Pump  No.  Cylinder  B.  h.p. 

Diameter  of  Cylinder.  26  ; Diameterof  Rod  S/z  ; Stroke  JZ — ; Clearance 

Date  May  „ .189 6 ; Time  ; End  of  Cylinder  ; Scale.of  Spring  SO. 

Boiler  Gauge  J07\  Vacuum  Gauge  26 ?/+..  . Rev,  per  minute  2f.'/z 

A - 

/ 

M Z 


Peoria  Water  Co.,  Peoria  Water  Co. 

PEORIA,  ILL.  PEORIA,  ILL. 

INDICATOR  CARD  INDICATOR  CARD 


/O 


W / S / e/e 


/&  (S)  •#  / S rc/e 

Diagram  from  Pump  No.  6/2  Cylinder  n,L.r. 

Diameter  of  Cylinder  SO  ; Diameter  of  Rod  ; Stroke  37. ; Clearance 

Date- 189^  ; Time  4&m..  ; End  of  Cylinder ; Scale  of  Spring 2.0... 


Boiler  Gauge  /V6  . ; Vacuum  Gauge  263/4 ; Rev.  per  minute.. 2.2. 

2 = J.  23 
L . . 4.  39 


20  (f)  * / 6,  c/e 

Diagram  from  Pump  No . 6/2  Cylinder  b.l.p. 

Diameter  of  Cylinder  SO  , Diameter  of  Rod  S/z  , Stroke  *37  ....,  Clearance  ....  : 

Date  .Mary /£/*.. 189^  , Time4ri/  ; End  of  Cylinder  ; Scale  of  Spring  20 ; 

Boiler  Gauge.  /06  ....  ; Vacuum  Gauge  .26?M~  ; Rev.  per  minute  2/. 

2i  3 60 

L 4 40 


9 


gases,  and  the  pressure  on  the  two  boiler  gauges.  Two  weighed  the 
feed-water,  checking  each  other’s  observations,  and  recorded  the  read- 
ings of  the  hot  and  cold  water  meters  and  the  thermometers  set  on 
the  lines  leading  from  hot  well  to  barrels,  from  barrels  to  heater,  and 
from  heater  into  boilers.  Two  made  the  calorimeter  tests.  Two  took 
indicator  cards.  The  engineer  on  regular  duty  during  the  test  noted 
every  fifteen  minutes  the  reading  of  the  counter  and  of  the  steam, 
water  and  vacuum  gauges  on  the  main  engine,  and  as  often  as 
possible  measured  the  stroke  of  the  main  engine;  recorded  the  air 
pressure  on  accumulator  tank,  the  speed  of  the  condenser  pump  No. 
io,  and  the  pressure  on  the  counter-charge  side  of  the  accumulator. 
He  also  recorded  the  time  of  starting  and  stopping,  and  the  speed  of 
such  auxiliaries  as  were  used  from  time  to  time.  An  observer  at  the 
reservoir  kept  records  of  the  stage  of  water  there;  another  noted  the 
level  of  the  water  in  the  well  every  fifteen  minutes,  and  struck  the 
signals  on  the  gong  which  notified  the  other  observers  of  the  instant 
at  which  readings  were  to  be  taken,  while  the  writer  gave  general  at- 
tention and  supervision  to  the  various  departments. 

After  a three  hours’  preliminary  run,  in  which  all  hands  were 
given  the  needed  practice  and  drilling  in  their  several  duties,  the  test 
was  begun  at  noon  on  May  15th,  1896,  and  was  continued  for  seven 
hours. 

The  test  was  started  with  a four-inch  clean  fire  on  the  grates,  the 
ash-pits  being  cleaned  immediately  after  starting.  The  steam  press- 
ure was  at  its  normal,  and  the  level  of  water  in  the  boilers  was  marked 
by  strings  tied  around  the  water  glasses.  The  test  was  closed  with 
the  fires,  steam  and  water  under  the  same  conditions  as  at  the  start, 
and  the  water  level,  draught  and  steam  pressure  were  kept  as  constant 
as  possible  during  the  trial. 

I take  this  occasion  to  acknowledge,  with  thanks,  the  valuable  as- 
sistance rendered  during  the  test  by  Messrs.  Jacob  A.  Harman,  C.  E., 
Peoria;  Ralph  P.  Browei,  Class  ’97,  Civil  Engineers,  U.  of  111.,  and 
J.  T.  Stewart,  of  Peoria. 

The  following  are  the  principal  dimensions  of  boilers,  engines 
and  auxiliaries,  and  the  record  of  the  test: 

OWNERS  OF  PLANT,  PEORIA  WATER  COMPANY,  PEORIA,  ILLINOIS. 

Date  of  Trial,  May  15th,  1896;  Duration  of  Trial,  Seven  Hours; 

Principal  Dimensions  of  Boilers,  Flues,  Stack,  Etc. 

1.  Boilers  Nos.  5 and  6,  each — - 

87  Tubes,  3^-inch  outside  diameter,  16  ft.  long  1,276.3  sq.  ft. 


2 Water-legs  (heated  on  one  side  only) 35.0 

y2  of  main  drum,  16x4  ft 73.0 


Total  heating  surface  each  boiler 1,384.3  sq.  ft. 

“ “ “ both  boilers 2,768.6  u 


IO 


2.  Grate  surface  each  boiler,  4 ft.  5 in.x6  ft.  7 in.  . . 29.04  sq.  ft. 

“ u both  boilers 58.08  “ 

Rocking  grate  bars,  9 rows  of  bars,  12  bars  to 
one  foot;  space  between  each  pair  of  bars, 
on  top,  about  equal  to  width  of  one  bar. 

3.  Ratio  of  heating  surface  to  grate  surface 47.67 

4.  Super-heating  surface,  none 0.00 

5.  Cross-section  of  stack,  5 ft.  4 in.  square 28.44  sq.  ft. 

Height  of  stack  above  boiler  room  floor 155.00  feet. 

“ “ “ “ grates 153.00  “ 

6.  Cross-section  of  flue  where  it  enters  stack 32.00  sq.  ft. 

“ “ “ between  boilers  Nos.  4 and 

5,  where  door  was  put  in  to  shut  off  air 29.50  “ 

7.  Principal  dimensions  of  engine  No.  612,  Worth- 

ington Compound  Duplex  Vertical  High  Duty 
Pumping  Engine — 

Diameter  of  high  pressure  cylinders  (2)..  . 25  inches 

“ “ low  “ u . . . 50  “ 

<c  “ water  plungers  (2) 21 

u <c  steam  piston-rod,  between  high 

pressure  and  low  pressure  pistons 5 “ 

Diameter  of  steam  piston-rod  below  low 

pressure  piston 514  “ 

Diameter  of  plunger  rod 51^  “ 

Average  stroke  for  whole  7 hours 3.09  feet 


PRINCIPAL  DIMENSIONS  OF  AUXILIARIES. 

8.  Pump  No.  1.  — Boiler  Feeder,  Worthington  Horizontal  Duplex, 

51^ -inch  and  314 -inch  by  5-inch  stroke.  Ran  constantly  at  83 
complete  strokes  per  minute,  pumping  water  from  weighing 
barrels  into  boilers,  against  a pressure  of  103.45  lbs.,  plus  the 
friction  in  pipes. 

9.  Pump  No.  2. — Boiler  Feeder,  same  make  and  dimensions  as  No. 

1.  Ran  intermittently  lifting  water  when  necessary  from  hot 
well  into  weighing  barrels.  Total  time  of  running,  140  min- 
utes, averaging  60  strokes  per  minute. 

10.  Pump  No.  5—  Worthington  Horizontal  Duplex  Air  and  Water 

Pump,  with  i^-inch  water  plungers  connected  by  yoke  to  main 
piston-rods.  Dimensions,  51^-inch  and  34^  inch,  and  5/Q-inch 
by  5-inch  stroke.  Ran  14  minutes  at  71  complete  strokes  per 
minute,  pumping  111.2  cubic  feet  of  free  air  against  pressure 
of  1 16  lbs.,  and  68  cubic  feet  of  water  against  pressure  of 
758  lbs. 

11.  Pump  No.  6. — Jacket  Pump.  Worthington  Horizontal  Duplex, 

3 inches  and  2 inches  by  3-inch  stroke.  Ran  continuously 
during  test,  averaging  2714  strokes  per  minute,  pumping  5,390 
lbs.  of  condensed  jacket  steam  into  boilers. 


i i 

12.  Purnp  No.  io. — Condenser  Pump.  Worthington  Horizontal 

Duplex  Air  Pump.  Ran  continuously  during  test  at  37.5 
complete  strokes  per  minute,  creating  an  average  vacuum  in 
condensers  of  25.34  inches,  and  lifting  43,316  lbs.  of  condensed 
steam  a vertical  distance  of  35  feet  into  hot  well. 

13.  Pump  No.  11. — Two-stage  Air  Compressor.  New  York  Air 

Brake  Co.’s  No.  3 Duplex  Pump,  with  two  steam  cylinders 
7 inches  in  diameter,  one  air  cylinder  5 inches  in  diameter  and 
the  other  air  cylinder  7 inches  in  diameter,  and  a stroke  of  9 
inches,  common  to  all  four  pistons.  Ran  intermittently  a total 
of  65  minutes  during  test,  averaging  18.5  complete  strokes  per 
minute.  Compressed  720  cu.  ft.  of  free  air  to  a pressure  of 
1 16  lbs. 


14.  Steam  pressure  on  boilers  by  gauge 103.45  lbs. 

15.  Absolute  steam  pressure  (barometer  14.67  lbs.) 118.12  “ 

16.  Force  of  draught  in  inches  of  water  (natural  draught)  0.60  in. 


AVERAGE  TEMPERATURES. 


17.  External  air  . . 

18.  Fire  room .... 

19.  Steam 

20.  Escaping  gases 

21.  Feed-water  . . . 


75-5°  Fahr- 
85.0°  “ 

339-8°  “ 

389.9“  “ 

I90. 2°  “ 


Fuel. — Bituminous  run  of  mine  coal,  from  Athens,  111. 


22.  Total  coal  consumed 9,298  lbs. 

23.  Moisture,  7.45  per  cent 693  “ 

24.  Dry  coal  consumed 8,605  “ 

25.  Total  refuse — 1,046  plus  38 1,084  “ 

26.  Total  combustible 7,521  “ 

By  Ultimate  By  Proximate 

Analysis.  Analysis. 

27.  Heating  value  of  1 lb.  coal. . . . 9,750  B.T.U.  10,830  B.T.U. 

28.  “ “ “ dry  coal  10,535  “ 11,700  “ 

29.  “ “ “ combust- 

ible  ...  12,053  “ i3-389  “ 

30.  Total  heat  in  fuel 90,655,500  u 100,697,340  “ 


RESULTS  OF  CALORIMETRIC  TEST. 

31.  Quality  of  steam  (dry) 


1. 00 


WATER. 


32.  Weight  of  jacket  steam  returned 

to  boilers 

33.  Weight  of  water  pumped  to 

boilers 

34.  Total  wt.  of  water  fed  to  boilers 

at  190.20  F.  (This  includes 
5,035  lbs.  of  fresh  feed-water 
fed  into  hot  well  from  water 
mains,  to  make  up  losses  by 
leakage,  etc.) 

35.  Estimated  leakage  from  blow-off 

cocks  and  flues,  in  water,  at 
339-8°  F . 

36.  Total  heat  above  o°  F.  in  the 

53,008  lbs.  of  water  actually 
evaporated,  at  103.45  lbs.  Pres* 
sure 

37.  Total  heat  derived  from  fuel, 

64,542,541  less  10,638,626, 
plus  935,000,  equals 


5,376  lbs. 
5(3,382  “ 


55,758  lbs. 

2,75°  “ 


10,638,626  B.T.U 


935,000  “ 


64>542>54i  “ 

54,838,915  “ 


Of  this  total  heat,  a portion  was  used  to  drive  the  main  pumping 
engine  No.  612;  the  remainder  was  expended  in  driving  the  several 
auxiliaries,  or  lost  by  leakage,  condensation,  radiation,  etc. 

This  total  heat  the  writer  has  divided  into  three  classes,  as  fol- 
lows: 


Class  A. — Expenditures  or  losses  of  heat  properly  chargeable  to 
boilers,  and  which  should  be  deducted  from  the  total  heat  de- 
rived by  them  from  the  fuel  (Item  37)  before  calculating  their 
net  evaporation  or  efficiency. 


38.  Heat  used  by  boiler  feeder  No.  1,  as  follows — 

B.T.U. 

Heat  in  3,381  lbs.  steam,  delivered 

to  pump  No.  1,  at  boiler  pressure  4,116,706 
Heat  in  exhaust  from  pump  No.  1,  3,636,780 


Net  heat  used  by  boiler  feeder 

No.  1 479,926 

39.  Heat  lost  by  condensation,  as  shown 
by  water  returned  by  steam  trap, 
as  follows — 

Heat  originally  in  1,105.5  lbs.  of 
water  and  steam  returned,  at 
boiler  pressure 1,346,057 


B.T.U. 


479,926 


13 

Heat  in  water  and  steam,  as  re- 
turned by  traps 

36i,743 

Net  heat  lost  by  condensation,  etc. 

984,3' 4 

984>3 '4 

40.  Heat  in  water  leaking  from  blow-off 
valves  and  flues  in  boilers,  2,750  lbs. 
at  340°  F 

935, 000 

41.  One-half  of  heat  lost  by  leaky  valve- 
stem  on  main  line — 

Total  heat  in  steam,  10  lbs.,  at 

103.45  lbs; 

Total  heat  in  water,  25  lbs.,  at 

34°°  F 

12,176 

8,500 

One-half  of  this 

20,676  equals 

io,338 

42.  One-half  of  leakage  through  valve  to 
pump  No.  8,  160  lbs.  steam  at  boiler 

pressure 

One-half  of  this 

194,826 

97,413 

43.  One-half  of  heat  lost  in  overflow  and 
blow-off  of  hot  well,  1,000  lbs. 
steam  at  atmospheric  pressure  .... 
200  lbs.  water  at  140°  F 

1,178,910 

28,000 

Total  loss 

One-half  of  this 

1,206,9 10 

6o3,455 

44.  One-half  of  heat  lost  by  radiation  and 
other  losses  not  accounted  for. 

Total  such  losses 

One-half  of  this 

2,526,978 

1,263,489 

45.  Total  heat  Class  A,  B.  T.  U. . . . 

4,373,935 

Class  B. — Expenditures  of  losses  of  heat  properly  chargeable  to 
pumping  engines,  and  which  should  be  added  together  before 
calculating  the  net  duty  or  efficiency  of  the  pump  No.  612. 

46.  Heat  used  by  No.  612  pump  in  steam  B.T.U. 
cylinders,  34,428.8  lbs.  of  dry  steam  at 

boiler  pressure  containing 41,920,507 

Heat  returned  in  condensed  steam  water 

at  55°  F 1,893,584 

B.T.U. 

Net 


40,026,923  40,026,923 


4 


47 • Heat  in  jacket  steam,  5,376  lbs.  Jacket 

steam  containing 6,545,817 

Heat  returned  in  condensed  jacket  steam  235?3 1 3 


Net  heat 6,310,504 

48.  Heat  used  by  air  compressor  No.  5,  65.4 

lbs.  steam,  containing 79,63  r 

Heat  in  exhaust  steam 64,103 


Net  heat  used 1 5,5 28 

49.  Heat  used  by  jacket  pump  No.  6,  84.0 

lbs.  steam,  containing 102,278 

Heat  in  exhaust  steam 22,375 


Net  heat  used 79,903 

50.  Heat  used  by  vacuum  pump  No.  10, 

2,758  lbs.  steam,  containing 3,358,141 

Heat  in  exhaust 2,460,108 


Net  heat  used 898,033 

51.  Heat  used  by  air  pump  No.  11,  333.3  lbs. 

steam,  containing 405,826 

Heat  in  exhaust 356,864 


Net  heat  used 48,962 

52.  Heat  lost  by  condensation  in  lines  to  aux- 
iliaries, etc.,  in  steam  leaking  past 


valves  and  stuffing  boxes,  blown  off  at 
cylinder  cocks,  etc.,  570  lbs.,  contain- 
ing 694,032  (B.  T.  U.) 

53.  One-half  of  heat  lost  by  leaky  valve  stem 

on  main  line.  (See  item  41 ) 

54.  One-half  of  heat  lost  by  leak  in  valve  to 

pump  No.  8.  (See  item  42) 

55.  One-half  of  heat  lost  in  overflow  and 

blow-off  of  hot  well.  (See  item  43). 

56.  One-half  of  heat  lost  by  radiation  and 

other  losses  not  accounted  for.  (See 
item  44) 

57.  Total  heat  Class  B in  B.  T.  U 

Class  C. — Expenditures  or  losses  of  heat  incident  only  to 
and  which  are  not  properly  chargeable  either  to 
engines. 


6>3I0>504 

•5.528 

79.9°3 

898.°33 

48,962 

694,032 

10,338 

97)4*3 

603.455 

1,263,489 

50,048,580 

these  tests, 
boilers  or 


5 


B.T.U. 

58.  Heat  lost  in  steam  consumed  by  calorimeter, 


310  lbs.,  containing 377H56  377H56 

59.  Heat  lost  in  steam  used  to  take  indicator 

cards,  10  lbs.  at  43  lbs.,  containing 1 1 ,967  11,967 

60.  Heat  used  by  boiler  feeder  No.  2,  441  lbs. 

steam,  containing 536,962 

Heat  in  exhaust  steam 509,985 


Net  heat  used 26,977  26,977 


61.  Total  heat,  Class  C,  in  B.  T.  U 416,400 


62. 


63- 


64. 

*5- 

66. 

67. 

68. 


69. 

7°. 

71- 

72- 


Total  of  Classes  A,  B and  C,  4,373,935  plus 
50,048,580,  plus  416,400,  equal  to  total 
heat  derived  from  fuel  by  boilers 

Item  37) 

Efficiency  of  furnaces  and  boilers  with- 
out allowing  for  any  losses,  figured 
from  total  heat  derived  from  fuel 
as  follows — 

Item  37  . , 

equals. 60.49  per  ct. 


(see 


By  Ultimate 
Analysis. 


54»838»9 '5 


By  Proximate 
Analysis. 

54.46  per  ct. 


Item  30 

Gross  evaporation  from  and  at  actual  temperatures 

and  pressures,  per  lb.  of  dry  coal 6.16  lbs. 

Gross  equivalent  evaporation  from  and  at  2120  F.  per 

lb.  of  dry  coal 6.60  u 

Gross  equivalent  evaporation  from  and  at  21 2°  F.  per 

lb.  of  combustible 7.51  “ 


Net  heat  derived  by  boilers  from  fuel  after  charging 
to  them  all  the  heat  under  Class  A,  54,838,915 

less  4,373,935,  equals 50,464,980 

Net  efficiency  of  furnaces  and  boilers,  Bj  ultimate  By  Proximate 
allowing  for  all  losses — Analysis.  Analysis. 

Item  67  . * 

— j- equals 55.67  per  ct.  50.12  per  ct. 

e m 3® 

Equivalent  net  evaporation  in  lbs.  of  water  from  ac- 
tual temperature  and  at  boiler  pressure 49,119  lbs. 

Equivalent  net  evaporation  in  lbs.  of  water  from  and 

at  2120  F 52,238  “ 

Net  evaporation,  after  allowing  for  heat  under  Class 
A from  and  at  actual  temperature  and  pressure  per 

lb.  of  dry  coal 5.71  “ 

Net  equivalent  evaporation  from  and  at  21 2°  F.  per 

lb.  of  dry  coal 6.07  “ 


6 


73-  Net  equivalent  evaporation  from  and  at  21 2°  F.  per 

lb.  of  combustible 6.91  lbs. 

RATES  OF  COMBUSTION  AND  EVAPORATION. 


74.  Dry  coal  actually  burned  per  square  foot  of  grate  sur- 

face per  hour 21.16  lbs. 

75.  Gross  rate  of  evaporation,  not  allowing  for  losses, 

from  and  at  21 2°  F.  per  square  foot  of  heating  sur- 
face per  hour 2.93  u 

76.  Net  rate  of  evaporation,  allowing  for  all  losses  under 

Class  A,  from  and  at  2120  F.  per  square  foot  of 
heating  surface  per  hour 2.69  “ 


COMMERCIAL  HORSE  POWER. 

77.  On  basis  of  30  lbs.  of  water  per  hour,  evaporated 

from  temperature  of  ioo°  F.  into  steam  at  70  lbs. 
gaugepressure(34^  lbs.  from  and  at2i2°  F.),  with- 
out allowing  for  losses  under  Class  A 236.8  H.P. 

78.  Same,  allowing  for  losses  under  Class  A 218.0  “ 

79.  Horse  power,  builders  rating  at  6.92  square  feet  heat- 

ing surface  per  H.  P 400.0  “ 

80.  Total  number  of  complete  strokes  or  revolutions  of 

pumping  engine  No.  612  during  trial 8,773 

81.  Total  number  of  gallons  of  water  pumped  during 

trial,  calculated  from  plunger  displacements 1,895,407 

PERCENTAGE  OF  SLIP. 

82.  Leakage  past  valves 0.17  per  ct. 

Leakage  past  plungers 2.48  “ 

Total  percentage  of  slip 2.65  per  ct.  2.65  per  ct. 

83.  Actual  gallons  pumped  during  trial  . . . 1,845,179 

84.  Head  against  which  water  was  pumped, 

elevation  in  reservoir  (316.24  ft.), 
less  elevation  in  well  (18.78  ft.),  plus 

friction  head  (6.93  ft.),  equals 304.39  ft. 

85.  Total  net  work  done  in  raising  water  by 

pumping  engine  during  trial 4,680,460,420  ft.  lbs. 

86.  Net  horse  power  of  pumping  engine 337*7  D.P. 

87.  Average  mean  effective  pressure  in  high  pressure 

cylinders,  taken  from  indicator  cards 40.61  lbs. 

88.  Average  mean  effective  pressure  in  low  pressure 

cylinders,  taken  from  indicator  cards 15*24  “ 

89.  Indicated  horse  power  of  pumping  engine  No.  612.  .384.41  H.P. 

90.  Engine  efficiency,  by  plunger  displacements 90.25  Per  ct* 


l7 


91.  Net  engine  efficiency,  deducting  slip — 

Item  86  337. 7 . 0 „ 

T -.--o'  ' - equals 87.83  per  ct. 

Item  89  384.41  H / D t' 

92.  Feed-water  from  and  at  2120  F.  corresponding  to  heat 

units  supplied  to  pumping  engine  and  auxiliaries, 
and  to  make  up  for  all  losses — 

Item  57  50,048,580  . 0 „ 

— = — equals  5 1,810  lbs. 

966  966  J 

93.  Equivalent  feed-water  from  and  at  21 20  F.  consumed 

per  net  horse  power  per  hour 21.91  “ 

94.  Equivalent  feed-water  from  and  at  2120  F.  consumed 

per  indicated  horse  power  per  hour 19.25  “ 

95.  Net  duty  of  pumping  engine,  allowing  for  all 

losses,  in  ft.  lbs.  per  1,000  lbs.  steam,  from 

and  at  2120  F 90,339,000  ft.  lbs. 

96.  Net  duty,  allowing  for  all  losses,  per  100  lbs. 

^ fuel 5°>337>3°° 

97.  Net  duty,  allowing  for  all  losses,  per  100  lbs. 

dry  coal 54,392,000 

98.  Net  duty,  allowing  for  all  losses,  per  1,000,000 

British  thermal  units 93,518,000  “ 


DISCUSSION  OF  RESULTS. 

Performance  of  Boilers  and  Furnaces. — Referring  to 
Item  63,  the  total  heat  derived  from  the  fuel  by  the  furnaces  and  boil- 
ers, divided  by  the  total  heat  in  the  fuel,  shows  an  efficiency,  not  al- 
lowing for  steam  for  boiler  feeder,  leakage,  and  all  other  losses,  of 
60.49  Per  cent*>  or  of  54.46  per  cent.,  according  to  whether  the  heat- 
ing value  of  the  fuel  is  figured  from  its  ultimate  or  proximate  analysis. 

Allowing  for  all  these  losses,  the  net  efficiency  would  be  55.67 
per  cent.,  or  50.12  per  cent.,  according  to  method  of  figuring  heating 
value  of  the  fuel. 

From  page  634  of  Kent’s  Mechanical  Engineers’  Pocket  Book, 
I quote  the  following: 

“ In  practice,  with  good  anthracite  coal,  in  a steam-boiler  per- 
fectly proportioned,  and  with  all  conditions  favorable,  it  is  possible  to 
obtain  in  the  steam  80  per  cent,  of  the  total  heat  of  combustion  of  the 
£oal.  * * * With  most  coals  of  the  Western  States,  it  is 

with  difficulty  that  as  much  as  60  per  cent,  or  65  per  cent,  of  the  the- 
oretical efficiency  can  be  obtained  without  the  use  of  gas  producers.” 

According  to  this,  the  gross  efficiency  of  from  54.46  per  cent,  to 
60.49  Per  cent.,  or  the  net  efficiency,  after  allowing  for  all  losses,  of 
from  50.12  per  cent,  to  55.67  per  cent.,  would  seem,  all  things  consid- 
ered, a fairly  good  performance  for  the  furnace  and  boilers,  in  view  of 
the  class  of  fuel  used  and  the  condition  of  the  boilers. 


i8 


Performance  of  PumpIng  Engine  No.  612. — Allowing  for 
all  losses  and  for  the  use  of  steam  by  the  necessary  auxiliaries,  the  net 
duty  per  1,000  lbs.  steam  from  and  at  2120  F.  is  seen  from  Item  95  to 
be  90,339,000  ft.  lbs.,  while  the  net  duty  per  1,000,000  British  ther- 
mal units,  is  93,518,000  ft.  lbs. 

While  the  writer  has  never  seen  the  specifications  for  these  pump- 
ing engines,  nor  any  record  of  a previous  duty  test,  it  has  always  been 
understood  that  the  engines  were  “ 100,000,000  duty  engines,”  and 
that  the  rating  was  based  on  a steam  pressure  of  115  lbs.  Extreme 
suction  lift  due  to  low  water  for  a long  period  previous  to  the  test,  and 
the  consequent  necessity  of  pumping  slowly,  had  resulted  in  carrying 
the  steam  at  the  pumping  station  at  a considerably  lower  pressure. 
The  test  was  made  at  this  lower  pressure.  With  115  pounds,  and  a 
slightly  higher  piston  speed,  it  is  altogether  likely  that  the  net  duty 
would  have  been  not  less  than  98,000,000  ft.  lbs.  per  1,000  lbs. 'steam 
from  and  at  21 20  Fahr.,  or  101,000,000  ft.  lbs.  per  1,000,000  British 
thermal  units. 

The  slip  of  2.65  per  cent.  (Item  82),  nearly  all  of  which  was  past 
the  water  plunger,  is  due  to  the  wear  of  the  plungers  and  plunger  bar- 
rels, and  their  corrosion  by  the  water  during  the  six  years  they  have 
been  in  service.  This  is  not  excessive.  If  the  pumps  were  new 
the  slip  would  probably  be  less  than  1 per  cent.  Under  these  cir- 
cumstances, and  with  steam  and  cut-offs  at  most  economical  points, 
they  would  have  shown  a net  duty  of  from  1 per  cent,  (if  calculated 
from  steam  from  and  at  2120  Fahr.)  to  3 per  cent,  (if  calculated  per 
1,000,000  B.  T.  U.)  in  excess  of  their  rating. 

The  losses  in  Items  41,  42,  43  and  44,  and  53,  54,  55  and  56, 
amount  to  3,949,390  B.  T.  U.,  or  7.2  per  cent,  of  the  total  heat  de- 
rived from  the  fuel  by  the  boilers.  These  losses,  resulting  from  leaks, 
radiation,  condensation,  etc.,  principally  in  the  steam  pipe  system,  are 
really  due  in  great  measure  to  no  defects  either  in  pumps  or  boilers; 
but  as  they  were  part  of  the  actual  losses  in  the  operation  of  the  plant, 
they  have  been  divided  equally,  in  the  above  results,  between  the 
pumps  and  boilers. 

It  is  needless  to  say  that  in  tests  as  ordinarily  made,  neither  pumps 
nor  boilers  would  be  charged  with  these  losses,  and  in  comparing  the 
results  given  above  with  those  reported  in  other  tests,  this  should  be 
borne  in  mind,  and  the  proper  credit  should  be  given  to  the  boilers 
and  pumping  engines. 

In  the  light  of  the  information  furnished  by  the  tests,  the  follow-* 
ing  changes  were  made  in  the  feed- water  return  system. 

It  was  considered  of  first  importance  to  diminish  the  deposition 
of  scale  and  oil  in  the  boilers.  To  accomplish  this,  the  writer  decided 
to  use  as  much  condensed  steam,  and  as  little  fresh  feed-water,  as 
possible;  to  separate  the  oil  from  the  condensed  steam  (which  has  no 
scale-forming  ingredients) ; and  to  remove  the  carbonates  and  sul- 
phates from  the  fresh  feed- water  (which  has  no  oil),  treating  the  two 


19 


separately  before  allowing  them  to  mix  in  the  boilers.  With  a view 
to  reducing  the  losses  of  condensed  steam,  the  exhaust  of  the  electric 
light  engine  is  run  into  the  condenser  of  the  main  pumping  engine 
that  happens  to  be  working  at  the  time,  while  the  exhaust  from  pump 
No.  8 is  brought  into  the  hot  well.  These  exhausts  were  previously 
wasted.  The  capacity  of  the  hot  well  has  been  greatly  enlarged  by 
the  connection  with  it  of  two  large  tierces  set  against  the  rear  wall  of 
the  boiler  room.  It  was  at  first  hoped  that  these  tierces,  into  which 
the  condensed  steam  from  the  pumping  engines  is  pumped  before  it 
goes  to  the  hot  well,  might  serve  as  oil-traps  for  the  oil  in  this  water; 
but  a trial  showed  that  the  emulsion  of  the  oil  and  the  water  could 
not  be  separated  by  gravity.  Arrangements  are  now  made  to  remove 
as  much  of  the  oil  as  possible  by  filtration  in  the  tierces  themselves. 
A portion  of  the  oil  in  the  exhaust  steam  from  the  auxiliaries  is  re- 
moved by  the  Austen  separator  set  on  the  exhaust  pipe  line  from 
these  pumps  to  hot  well. 

The  fresh  feed-water  (which  has  been  reduced  at  this  writing  to 
from  2 to  4 per  cent,  of  the  total  feed-water),  is  forced  by  the  pressure 
in  the  mains,  through  a 50  H.  P.  Hoppes  live  steam  purifier,  pur- 
chased for  the  purpose,  which  removes  a considerable  portion  of  the 
salts  of  lime  and  magnesia.  The  advantage  of  treating  the  fresh  and 
condensed  feed-water  separately  will  be  apparent  when  it  is  remem- 
bered that  if  all  the  feed-water  had  to  be  treated  to  remove  the  salts, 
a purifier  of  800  H.  P.  would  have  been  required  to  do  the  work  now 
done,  and  with  a margin  to  spare,  by  the  one  of  50  H.  P. 

A Worthington  hot  water  meter  is  set  on  the  feed- water  line  from 
the  hot  well,  and  a small  Crown  meter  measures  the  fresh  feed-water 
before  it  goes  to  the  purifier.  This  little  meter  plays  an  important 
part  in  the  economical  operation  of  the  plant ; for  an  excess  in  its  registra- 
tion during  any  man’s  watch  means  either  that  pipes  or  valves  are 
leaking  or  that  the  man  has  been  negligent;  and  each  man  is  encour- 
aged to  reduce  the  meter  readings  to  a minimum.  Leaks  that  form- 
erly went  undetected  for  long  periods  — owing  to  the  very  large 
number  of  pipes  and  valves  in  the  system  — are  now  promptly  dis- 
covered. 

As  a result  of  these  changes,  the  boilers  now  show,  at  the  close 
of  six  weeks’  run,  not  more  than  1-32  inch  of  scale,  and  this  without 
the  use  of  any  boiler  compounds  whatever.  Automatic  lubricators  on 
all  auxiliaries  have  largely  reduced  the  oil  consumption,  and  a still 
further  saving  will  undoubtedly  be  effected  when  the  oil  filters  are  in 
operation.  The  tests  developed  the  fact  that  boiler  feeder  No.  1 had 
a slip  of  77.6  per  cent.,  due  to  blow-holes  in  plunger,  and  wear  in 
plungers  and  water  cylinders.  These  defects  have  been  remedied, 
and  the  slip  probably  does  not  now  exceed  25  per  cent. 

A system  of  flue  gas  tests  under  different  conditions  of  draught, 
air-admission,  and  firing,  will  probably  result  in  some  slight  economy 
in  coal. 


20 


It  is  estimated  that  the  savings  in  fuel  from  these  flue  gas  tests; 
from  the  changes  in  steam  pressure  and  cut-off;  from  the  removal  of 
scale  from  the  boilers  and  the  repairs  to  boiler  feeder  No.  i,  will  re- 
sult in  a saving  of  from  io  per  cent,  to  15  per  cent,  of  the  coal  bill  — 
or,  say,  $450  per  annum.  The  saving  in  boiler  compound  will 
amount  to  $175  more,  and  the  yearly  saving  in  oil  to  perhaps  $50  — 
or  a total  of  $675  per  annum.  The  total  cost  of  the  test  and  testing 
instruments,  including  thermometers,  mercury  column;  flue  gas 
sampler  and  apparatus  for  gas  analysis;  iron  door  in  breeching  or 
flue;  standardization  of  instruments;  all  labor  and  materials  of  every 
sort,  and  oculist’s  bill  for  treatment  of  two  engineers  whose  eyes  were 
injured  while  testing  thermometers,  was  $250.20.  The  cost  of  the 
changes  in  the  feed-water  returns;  additions  to  the  hot  well;  the 
Hoppes  feed-water  purifier,  and  all  other  changes  of  every  sort  in  the 
system,  was  $410.14.  All  of  this  latter  amount,  as  well  as  such  por- 
tion of  the  $250.20  as  was  invested  in  instruments  or  apparatus  still 
in  stock,  may  be  considered  as  spent  in  permanent  improvements  to 
the  plant.  The  total  of  all  the  expenditures  was  $660.34.  The 
economies  resulting,  not  counting  the  improvement  in  discipline  and 
education  of  the  Pumping  Station  force,  nor  the  general  benefits  in 
added  life  of  boilers  and  improvement  of  plant,  will  probably  give  a 
return  of  100  per  cent,  on  the  investment  in  the  first  year,  and  would 
have  been  proportionately  greater  had  the  operation  of  the  plant  been 
less  economical  than  the  tests  showed  it  to  be. 


\ 


